I think your really confused when it comes to the status of TCX Thomas Cook Airlines! Newcastle may or may not recognise it as a scheduled airline but I can assure you that other than the transatlantic operation out of Manchester it is very much a charter airline, you can't even book any of their charter flights through a GDS other than seat only on the Thomas Cook Holidays website.
I have no issue booking any Thomas Cook flights through 3rd party websites, Google flights, they appear in GDS and so on.....